src/hotspot/os/aix/os_aix.cpp

*** 2489,2512 ****
  bool os::can_execute_large_page_memory() {
    // Does not matter, we do not support huge pages.
    return false;
  }
  
  // Reserve memory at an arbitrary address, only if that area is
  // available (and not reserved for something else).
! char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr, bool use_SHM) {
    char* addr = NULL;
  
    // Always round to os::vm_page_size(), which may be larger than 4K.
    bytes = align_up(bytes, os::vm_page_size());
  
    // In 4K mode always use mmap.
    // In 64K mode allocate small sizes with mmap, large ones with 64K shmatted.
    if (os::vm_page_size() == 4*K) {
      return reserve_mmaped_memory(bytes, requested_addr, 0);
    } else {
!     if (use_SHM && bytes >= Use64KPagesThreshold) {
        return reserve_shmated_memory(bytes, requested_addr, 0);
      } else {
        return reserve_mmaped_memory(bytes, requested_addr, 0);
      }
    }
--- 2489,2528 ----
  bool os::can_execute_large_page_memory() {
    // Does not matter, we do not support huge pages.
    return false;
  }
  
+ char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr, int file_desc) {
+   assert(file_desc >= 0, "file_desc is not valid");
+   char* result = NULL;
+ 
+   // Always round to os::vm_page_size(), which may be larger than 4K.
+   bytes = align_up(bytes, os::vm_page_size());
+   result = reserve_mmaped_memory(bytes, requested_addr, 0);
+   
+   if (result != NULL) {
+     if (replace_existing_mapping_with_dax_file_mapping(result, bytes, file_desc) == NULL) {
+       vm_exit_during_initialization(err_msg("Error in mapping Java heap at the given filesystem directory"));
+     }
+   }
+   return result;
+ }
+ 
  // Reserve memory at an arbitrary address, only if that area is
  // available (and not reserved for something else).
! char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
    char* addr = NULL;
  
    // Always round to os::vm_page_size(), which may be larger than 4K.
    bytes = align_up(bytes, os::vm_page_size());
  
    // In 4K mode always use mmap.
    // In 64K mode allocate small sizes with mmap, large ones with 64K shmatted.
    if (os::vm_page_size() == 4*K) {
      return reserve_mmaped_memory(bytes, requested_addr, 0);
    } else {
!     if (bytes >= Use64KPagesThreshold) {
        return reserve_shmated_memory(bytes, requested_addr, 0);
      } else {
        return reserve_mmaped_memory(bytes, requested_addr, 0);
      }
    }